Insertable robot for minimally invasive surgery

ABSTRACT

An insertable robot for minimally invasive surgery includes a tube array having a guide tube housed within a straightening tube. The guide tube includes a curved working end. The guide tube may be axially translated and rotated relative to the straightening tube such that the curved working end is constrained inside the straightening tube, causing the curved working end to achieve a smaller dimension. The tube array is inserted into a working channel on an endoscope, resectoscope or trocar. Once the tube array is inserted, the curved working end of the guide tube is translated forward beyond the distal end of the working channel, allowing the curved working end to return to its pre-formed shape. A surgical tool is inserted through the guide tube for an operation. The straightening tube allows the guide tube curved working end to be temporarily straightened during insertion and removal of the tube array.

CROSS-REFERENCES TO RELATED APPLICATIONS

This invention was made with government support under R44EB024423awarded by the National Institutes of Health. The government has certainrights in the invention.

BACKGROUND

The present invention relates to surgical instruments and associatedmethods for performing surgery. More particularly, the present inventionrelates to tools and methods for minimally invasive surgery usingconcentric tube robot assemblies.

Minimally invasive surgery using electromechanical robots is adeveloping field of medicine. Conventional devices for performingminimally invasive surgery, such as endoscopes and resectoscopes,generally include a distal tip that is inserted through an incision in apatient's body or a natural orifice in a patient's body. The distal tipincludes an optical lens which allows a surgeon to see a field of viewproximate to the distal tip when placed inside the body. The endoscopewill typically have a camera attached to it to display the field of viewon an operating room monitor. In some applications the endoscopeincludes a camera installed on the distal tip of the endoscope. Thedevice also includes a working channel extending through the device. Oneor more elongated surgical tools may be inserted through the workingchannel. A tool such as a cutting device, a basket or a laser optic maybe included on the surgical tool. The distal end of the surgical toolprotrudes from the distal tip of the device, thereby allowing thesurgeon to visually observe operation of the tool inside the patient'sbody during an operation.

Conventional surgical tools for use through the narrow working channelof an endoscope or resectoscope are generally limited in size, and areparticularly limited in the maximum effective outer diameter. Becausesuch tools must be passed through the working channel to reach thesurgical site inside the body, the tools must be small enough in outerdiameter to be inserted axially into the bore of a working channel in anendoscope or resectoscope. The working channel diameter in an endoscopeor resectoscope is generally in the range of about one to twentymillimeters, but the devices may have different inner diameters outsideof this range depending on the application. Thus, a surgical tool to beinserted through the working channel must include a similar, or asmaller, effective outer diameter to be smoothly inserted through thechannel to reach the surgical site.

During a surgical procedure, it may become necessary to change asurgical tool. For example, a laser cutting fiber may need to be removedfrom the endoscope or resectoscope via the working channel, and amechanical manipulator may need to be inserted through the workingchannel. Manipulators allow a surgeon to move the distal end of thesurgical tool protruding from the distal tip of the endoscope withoutactually moving the endoscope. This may reduce trauma on the patient insome applications.

When a surgical tool is changed during a procedure, a first tool may beslid axially out of the working channel in a direction away from thepatient, and a second tool may be slid axially into the working channel,or inserted into the working channel, in a direction toward the patient.The second tool is inserted until the distal end of the working tool isin a position to advance toward the surgical site. However, if the firstor second surgical tool has a highly curved distal end, or a distal endwith a large expanded profile, the second tool may not properly fit intothe working channel. Thus, it may be difficult or impossible to insertthe surgical tool with a curved or large profile tip into the workingchannel toward the patient.

What is needed then are improvements in devices and methods forperforming robotic surgery.

BRIEF SUMMARY

The present invention relates generally to devices and methods forperforming minimally invasive surgery. In some embodiments, the presentinvention includes a surgical robot apparatus including a guide tubewith a curved working end housed inside a straightening tube, whereinthe straightening tube at least partially straightens the curved workingend of the guide tube such that the guide tube and straightening tubemay be inserted simultaneously as a combined assembly through the smalldiameter working channel of the shaft on an endoscope, resectoscope ortrocar. In various embodiments, the assembly may include additionaltubes, such as an inner tube passing through the guide tube in additionto the surgical tool.

Following insertion of the guide tube and straightening tube into theworking channel, the guide tube may be axially translated through thestraightening tube toward a patient's body allowing the curved workingend to extend from the distal end of the straightening tube and assumeits naturally biased curved orientation. A surgical tool such as a laseroptic, cutting tool, forceps, basket or other instrument is passedaxially through the guide tube extending from the distal tip of theguide tube. The curvature of the guide tube allows a surgeon improvedrange of motion for the surgical tool inside the patient's body, whencompared with traditional straight surgical tools. The guide tube iscoupled to a transmission that allows the guide tube to be translated orrotated during a procedure to steer the surgical tool to desired tissue.

In some embodiments, the present invention includes a concentric tuberobot apparatus for performing minimally invasive surgery. The apparatusincludes a tube array with a guide tube and a straightening tube. Theguide tube includes a curved working end. The guide tube may betranslated and rotated relative to the straightening tube such that thecurved working end is housed inside and constrained by the straighteningtube, thereby allowing the tube array to be inserted into a narrowworking channel of an endoscope, resectoscope or trocar. A transmissionis also coupled to the tube array in some embodiments, providing aninterchangeable cartridge configuration that can be installed or removedas a complete unit on a surgical robot during a procedure.

One objective of the present disclosure is to provide a surgical robotapparatus that allows a user to change surgical tools during surgerywithout removing the endoscope, resectoscope or trocar shaft from thepatient's body.

Another objective of the present disclosure is to provide a surgicalrobot apparatus that allows a guide tube with a highly curved workingend to be inserted axially through a narrow working channel on anendoscope, resectoscope or trocar.

A further objective of the present disclosure is to provide a surgicalrobot apparatus that includes a modular tube array with an integratedsurgical tool that can be quickly changed during a surgical procedure bysliding the tube array into or out of a longitudinal straight orslightly curved working channel on a stationary endoscope, resectoscopeor trocar.

Numerous other objects, features and advantages of the present inventionwill be readily apparent to those skilled in the art upon a reading ofthe following disclosure when taken in conjunction with the accompanyingdrawings and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective view of a prior art embodiment of anendoscope including a surgical tool with an end effector protruding fromthe distal tip.

FIG. 2A illustrates a detail perspective view of a prior art embodimentof an endoscope distal tip with a lens and a working channel openingbelow the lens.

FIG. 2B illustrates a detail cutaway perspective view of the prior artembodiment of an endoscope of FIG. 2A with a surgical tool and endeffector protruding from the distal tip.

FIG. 3 illustrates a perspective view of a prior art embodiment of anendoscope with separate concentric tube manipulator assembliesprotruding from the distal tip.

FIG. 4 illustrates a perspective view of an embodiment of a guide tubewith a curved distal end.

FIG. 5 illustrates a partial perspective view of an embodiment of aguide tube with a distal end being positioned inside a straighteningtube.

FIG. 6 illustrates a partial perspective view of the embodiment of aguide tube in FIG. 5 positioned inside the straightening tube such thata portion of the curved distal end of the guide tube is received insideand straightened by the straightening tube.

FIG. 7 illustrates a cross-sectional view of an embodiment of a guidetube with a curved distal end housed inside a straightening tube.

FIG. 8 illustrates a cross-sectional view of an embodiment of a guidetube with a curved distal end partially protruding from thestraightening tube.

FIG. 9 illustrates a partial cross-sectional view of an embodiment of anendoscope, resectoscope or trocar including a straightening tube, guidetube and surgical tool assembly partially inserted through the workingchannel.

FIG. 10 illustrates a partial cross-sectional view of an embodiment ofan endoscope, resectoscope or trocar including a straightening tube,guide tube and surgical tool assembly inserted through the workingchannel to a ready position.

FIG. 11 illustrates a partial cross-sectional view of an embodiment ofan endoscope, resectoscope or trocar including a straightening tube,guide tube and surgical tool assembly inserted through the workingchannel, with the guide tube and surgical tool partially extending fromthe straightening tube.

FIG. 12 illustrates a partial cross-sectional view of an embodiment ofan endoscope, resectoscope or trocar including a straightening tube,guide tube and surgical tool assembly inserted through the workingchannel, with the guide tube and surgical tool partially extending fromthe straightening tube.

FIG. 13 illustrates a partial cross-sectional view of an embodiment ofan endoscope, resectoscope or trocar including a straightening tube,guide tube and surgical tool assembly inserted through the workingchannel, with the guide tube extending from the straightening tube, andthe surgical tool extending from the guide tube.

FIG. 14 illustrates a partial cross-sectional view of an embodiment ofan endoscope, resectoscope or trocar including a straightening tube,guide tube and surgical tool assembly inserted through the workingchannel, with the guide tube and surgical tool partially extending fromthe straightening tube and rotated about the working channel axis.

FIG. 15 illustrates a partial cross-sectional view of an embodiment ofan endoscope, resectoscope or trocar including a straightening tube,guide tube and surgical tool assembly inserted through the workingchannel, with the guide tube partially extending from the straighteningtube and rotated about the working channel axis and the surgical toolextending from the guide tube.

FIG. 16 illustrates a partial cross-sectional view of an embodiment ofan endoscope, resectoscope or trocar including a straightening tube,guide tube and surgical tool assembly partially inserted through theworking channel with an axial stop positioned to limit translation ofthe straightening tube to a desired position in the working channel.

FIG. 17 illustrates a partial cross-sectional view of the embodiment ofan endoscope, resectoscope or trocar of FIG. 16 including astraightening tube, guide tube and surgical tool assembly insertedthrough the working channel with the axial stop limiting translation ofthe straightening tube to a desired position in the working channel.

FIG. 18 illustrates a partial cross-sectional view of the embodiment ofan endoscope, resectoscope or trocar of FIGS. 16 and 17 including astraightening tube, guide tube and surgical tool assembly insertedthrough the working channel with the axial stop limiting translation ofthe straightening tube to a desired position in the working channel andthe guide tube and surgical tool extending from the straightening tube.

FIG. 19 illustrates a partial cross-sectional view of the embodiment ofan endoscope, resectoscope or trocar of FIGS. 16, 17 and 18 including astraightening tube, guide tube and surgical tool assembly insertedthrough the working channel with the axial stop limiting translation ofthe straightening tube to a desired position in the working channel, theguide tube extending from the straightening tube, and the surgical toolextending from the guide tube.

FIG. 20 illustrates a partial cross-sectional view of an alternativeembodiment of an endoscope, resectoscope or trocar including astraightening tube, guide tube and surgical tool assembly partiallyinserted through the working channel with an axial stop positioned tolimit translation of the straightening tube to a desired position in theworking channel.

FIG. 21 illustrates a partial cross-sectional view of the embodiment ofan endoscope, resectoscope or trocar of FIG. 20 including astraightening tube, guide tube and surgical tool assembly insertedthrough the working channel with the axial stop limiting translation ofthe straightening tube to a desired position in the working channel.

FIG. 22 illustrates a partial cross-sectional schematic view of anembodiment of a robotic assembly with a surgical tool, a guide tube anda straightening tube coupled to a transmission including guide tubetranslation and rotation and surgical tool translation and rotationdrives.

FIG. 23 illustrates a partial cross-sectional view of an embodiment of atube array with a transmission for insertion into a working channel.

FIG. 24 illustrates a partial cross-sectional view of an embodiment ofan endoscope with an insertion port at the proximal end of the workingchannel.

FIG. 25 illustrates a perspective view of an embodiment of aresectoscope including an optical lens partially inserted into theshaft.

FIG. 26 is a detail perspective view of Section 26 from FIG. 25 .

FIG. 27 illustrates a partial cross-sectional view of an embodiment ofan endoscope, resectoscope or trocar including first and second workingchannels and tube arrays.

FIG. 28 illustrates a partial cross-sectional view of an embodiment ofan endoscope, resectoscope or trocar including first and second workingchannels and tube arrays.

FIG. 29 illustrates a partial cross-sectional view of an embodiment ofsurgical robot assembly including first and second tube arrayspositioned in first and second working channels, each having a curvedworking end partially extended from its corresponding straighteningtube.

DETAILED DESCRIPTION

Referring now to the drawings, various views of embodiments of devicesand methods for performing minimally invasive surgery are illustrated.In the drawings, not all reference numbers are included in each drawing,for the sake of clarity. The devices shown in the illustrations are notintended to illustrate all possible embodiments of the claimedinvention, but are rather included as examples. A person of skill in theart will understand the devices and methods of the claimed invention mayinclude different configurations and orientations not shown in thefigures.

The present disclosure provides an insertable concentric tube assemblyfor minimally invasive surgery. During conventional minimally invasivesurgery, a surgical instrument such as an endoscope, resectoscope ortrocar includes a distal tip inserted into a patient's body through asmall incision. A surgical tool including an end effector such as acutting tool, probe, forceps, basket, laser fiber or other surgical toolprotrudes from the distal tip for performing an operation on patienttissue. An optical lens positioned proximate the distal tip allows asurgeon to visually observe the surgical tool in vivo during theoperation.

An example of a conventional endoscope device 10 for performingminimally invasive surgery is shown in FIG. 1 . The device 10 includes alongitudinal shaft 12 having a distal end 14 and a proximal end 16. Thelongitudinal shaft 12 includes a hollow interior allowing the passage ofone or more surgical instruments 20. Surgical instrument 20 includes asurgical tool with an end effector 22, such as a cutting tool orforceps, disposed on the distal tool end 26 as shown in FIG. 1 . Thesurgical instrument 20 includes a tool actuator 24 on one end and a toolshaft 28 extending from the tool actuator. The tool shaft 28 is insertedinto the longitudinal shaft 12 of the endoscope device 10 such that thedistal tool end 26 and the end effector 22 protrude from an opening atthe distal end 14 of the of the device 10.

During surgery, the distal end 14 of the device 10, together with thedistal tool end 26 and end effector 22 are inserted into a patient'sbody. The tool actuator 24 may then be manipulated to activate the endeffector 22, for example to perform a cutting operation to removepatient tissue from within the body. During this procedure, the surgicaltool 20 may be manipulated relative to the device 10 by moving thesurgical tool axially such that the tool shaft translates within thelongitudinal shaft 12, thereby moving the longitudinal position of theend effector 22 relative to the distal end 14 of the device 10.Additionally, the surgical instrument 20 may be rotated angularly aboutthe longitudinal axis of the shaft 12, thereby causing the end effector22 to rotate relative to the distal end 14 of the device 10.

During minimally invasive surgery, it is beneficial for a surgeon to beable to visually observe the position of the end effector 22 relative tothe tissue undergoing operation. As shown in FIG. 1 , endoscope device10 in some embodiments includes an optical port 30 for a camera or opticto be inserted into the device 10 such that the camera or optic extendsthrough the interior of the longitudinal shaft 12 alongside the toolshaft 28.

An example of a distal end 14 of a tubular, hollow longitudinal shaft 12of a conventional endoscope, resectoscope or trocar is shown in FIGS. 2Aand 2B. The longitudinal shaft 12 includes an end opening 19 at thedistal end 14. A hood 15 surrounds the end opening 19 in someembodiments. A working channel 18 is defined through the hollow interiorof the longitudinal shaft 12, and one or more tools may be passedthrough the working channel 18 toward the end opening 19. An opticallens 32 is positioned proximate the end opening 19 in some embodiments.The optical lens 32 is coupled to an optical fiber 34 to provide imagingcapabilities to a surgeon. The optical fiber 34 extends through theworking channel 18 of the longitudinal shaft 12.

Also shown in FIGS. 2A and 2B, a conventional tool shaft 28 extendsthrough the working channel 18 toward the end opening 19 at the distalend 14 of the longitudinal shaft 12. The tool shaft 28 is part of asurgical instrument that may be manipulated manually by a surgeon orteleoperated by a surgeon using a robotic interface to actuate endeffector 22 and to move distal tool end 26 axially or angularly relativeto tool shaft axis 29. During a procedure, tool shaft 28 may be axiallytranslated in and out of end opening 19 manually or using a mechanizedtransmission linkage coupled to the tool shaft 28. Additionally, duringa procedure, tool shaft 28 may also be rotated angularly about toolshaft axis 29 manually or using a transmission linkage coupled to thetool shaft 28.

Referring to FIG. 3 , in some embodiments, it is desirable to includetwo surgical tools 20 a, 20 b protruding from end opening 19. Each toolincludes an end effector that may be positioned using one or moreconcentric tubes 25 a, 25 b, 25 c, 25 d. Such configurations are knownin the art for allowing a surgeon to position and steer the endeffectors to a desired location at the surgery site. However, suchmultiple concentric tube configurations are generally fixed and are notinsertable through a working channel in an endoscope, resectoscope ortrocar due to the relatively large effective diameter of each concentrictube working end caused by the curvature of each tube. As such,conventional concentric tube assemblies for surgical robotics are notamenable to be interchanged by insertion and removal through a smalldiameter working channel in an endoscope, resectoscope or trocar.

An example of an elongated tube for guiding a surgical tool through aworking channel of an endoscope, resectoscope or trocar is shown in FIG.4 . The various tubes illustrated herein are not drawn to scale, and mayinclude various aspect ratios, lengths, inner diameters, outerdiameters, wall thicknesses and curvature profiles not shown. Person ofskill in the art will readily understand that the tubes disclosed hereinmay take many different embodiments in practice. A guide tube 50, orinner tube, is shown in FIG. 4 . Guide tube 50 includes a guide tubebody 52 and a curved working end 54 at the distal end of the guide tubebody 52. Guide tube 50 includes a hollow interior and may comprise anysuitable material such as a metal or metal alloy. In some embodiments,guide tube 50 comprises a nickel-titanium, or Nitinol, alloy. Guide tube50 is generally used to steer a surgical tool to a desired location at asurgical site at the distal tip of an endoscope, resectoscope or trocar.The surgical tool may be axially housed inside the guide tube 50, andthe surgical end effector may be deployed or retracted in vivo throughthe guide tube distal end opening 56.

The curved working end 54 of the guide tube 50 is pre-shaped to have adesired curvature profile. In some embodiments, the curvature profile ofthe curved working end 54 is optimized to provide maximum steerabilityof the surgical end effector in the field of view of the optical lens32.

One drawback of having a curved working end 54 on a guide tube 50 is thecurvature profile of the guide tube curved working end 54 causes theguide tube 50 to have an effective outer dimension, or effectivediameter, W. In most applications, the guide tube effective diameter Wis greater than a corresponding working channel inner diameter on anendoscope, resectoscope or trocar. Thus, it can be difficult orimpossible to insert or remove a guide tube 50 with a curved working end54 axially through the working channel.

As shown in FIGS. 5 to 7 , in some embodiments, an outer tube orstraightening tube 60 may be positioned over the outside of the guidetube 50. Straightening tube 60 includes a cylindrical tube with a hollowinterior. The inner diameter of the straightening tube 60 is slightlylarger than the outer diameter of the guide tube 50 such that the guidetube 50 fits closely inside the straightening tube 60 yet is still ableto translate axially and rotate relative to the straightening tube 60.As shown in FIG. 5 , straightening tube 60 includes a straightening tubedistal end 66 and a straightening tube distal end opening 68. The guidetube 50 is received in the straightening tube distal end opening 68.When the curved working end 54 of the guide tube 50 is translated intothe straightening tube 60, the curved working end 54 is deflected orstrained away from its biased curved position toward the guide tube axis51. When the curved working end 54 of the guide tube 50 is fully seatedinside the straightening tube 60, as shown in FIG. 7 , the guide tubedistal end opening 56 is axially aligned with the straightening tubedistal end 66. In this position, the curved working end 54 is alsoconstrained by the straightening tube such that the curved working end54 is significantly straightened. In such embodiments, the overalleffective outer diameter of the straightening tube distal end 66 and thecurved working end 54, D, is substantially equal to the outer diameterof the straightening tube 60.

In some embodiments, the curved working end 54 may impart a force on thestraightening tube distal end 66 causing the straightening tube distalend 66 to flex slightly. However, the strain placed on the straighteningtube is generally not significant enough to prevent the straighteningtube 60 from being able to be inserted through a working channel.

As shown in FIG. 8 , the guide tube 50 may be translated axially insidethe straightening tube 60 to expose a portion of the curved working end54 from the distal end of the straightening tube 66. As the guide tube50 is axially translated causing the curved working end 54 to protrudeout of the straightening tube distal end 66, the curved working end 54returns to its pre-curved biased position away from the straighteningtube axis 62. The orientation of the guide tube distal end opening 58 iscontrolled by precise translation and rotation of the guide tube 50 andthe straightening tube 60.

Referring to FIGS. 9 and 10 , guide tube 50 includes a guide tube body52 and guide tube curved working end 54 housed inside a straighteningtube 60. The guide tube and straightening tube assembly 50, 60 togetherincludes a dimensional profile allowing the assembly to be insertedthrough the working channel 18 defined by working channel inner wall 17.Working channel 18 includes an inner working channel diameter 38 formedin the longitudinal shaft 12 of the endoscope, resectoscope or trocar.Working channel 18 includes a distal end 19 including an opening formedat the distal tip of the working channel. The guide tube andstraightening tube assembly 50, 60 may be inserted through the workingchannel at the same time, as shown in FIG. 9 . Additionally, duringinsertion of the guide tube and straightening tube assembly 50, 60, asurgical tool having a surgical tool shaft 28 and surgical tool distalend 26 may also be housed inside the guide tube 50. During insertion ofthe guide tube and straightening tube assembly 50, 60, the guide tubedistal end 56 and straightening tube distal end 66 are axially alignedwith the surgical tool distal end 26 in some applications.

As shown in FIG. 10 , the guide tube and straightening tube assembly 50,60 is inserted through the working channel 18 until the guide tubedistal end 56 and straightening tube distal end 66 are axially alignedwith the working channel distal end 19. In this position, the surgicaltool distal end 26 is also axially aligned with the guide tube distalend 56 and straightening tube distal end 66. At this ready position,forward translation of the straightening tube 60 is limited; however,the guide tube 50 and surgical tool 20 may be translated in tandem orindependently axially relative to the stationary straightening tube 60as shown in FIG. 11 . The forward translation of the guide tube distalend 56 and straightening tube distal end 66 are controlled by a manualactuator or an electro-mechanical transmission linkage coupled to thetubes. As the guide tube distal end 56 and straightening tube distal end66 advance axially out of the opening at the distal end of thestraightening tube, the curved working end 54 of the guide tube 50returns to its pre-shaped curvature in its preferred biased position. Insome applications, the straightening tube distal end 66 may extendbeyond the working channel distal end 19 into the surgical field tofurther effect manipulation of the guide tube and surgical tool.

The guide tube angle 53 is a function of the axial position of the guidetube curved working end 54 relative to the straightening tube 60. As theguide tube 50 advances forward away from straightening tube 60, theguide tube angle 53 increases until the curved working end 54 assumesits fully biased curvature profile. When the guide tube 50 is retractedrelative to the straightening tube 60, the guide tube angle 53 decreasestoward a limit of zero in some embodiments as the curved working end 54is drawn into the straightening tube 60.

Once the guide tube 50 is translated and rotated into a desiredposition, for example as shown in FIG. 12 , the surgical tool 20 may bedeployed by axially translating the surgical tool shaft 28 through theguide tube 50. Such translation of the surgical tool shaft 28 causes thesurgical tool distal end 26 to protrude beyond the guide tube distal end56, as shown in FIG. 13 . In further embodiments, the surgical tooldistal end 26 is fixed to the guide tube distal end 56 such that thesurgical tool distal end 26 is not translatable axially relative to theguide tube 50.

As shown in FIGS. 14-15 , the guide tube may be subsequently rotatedand/or translated while also moving the axial position of the surgicaltool shaft 28 to maneuver the surgical tool distal end 26 to a desiredlocation. The ability to rotate and translate guide tube 50 relative tostraightening tube 60, combined with the ability to translate surgicaltool shaft 28 relative to guide tube 50, provides a technical solutionwith multiple degrees of freedom for enhancing steerability of thesurgical end effector inside the field of view of the lens 32.

Referring to FIGS. 16-19 , in some applications it is desirable to stopthe axial translation of the guide tube distal end 56 and straighteningtube distal end 66 at the distal end of the working channel. An axialstop 80 may be disposed on or linked to the straightening tube 60. Axialstop 80 can take many forms, including an annular flange protrudingradially from the proximal end of straightening tube 60. Axial stop 80interferes with a corresponding mechanical structure on the apparatuswhen the straightening tube distal end 66 is axially aligned with thedistal end of the working channel, as shown in FIG. 17 . The structureengaging axial stop 80 to limit forward travel of straightening tube 60may include a shoulder on the proximal end of the working channel 82 insome embodiments. When the axial stop 80 approaches and contacts theworking channel proximal end at a contact location 84, forward travel ofthe straightening tube 60 is stopped. From the position where thestraightening tube 60 is limited in forward travel by axial stop 80,guide tube proximal end 52 may be freely advanced forward relative tostationary straightening tube 60, thereby allowing the curved workingend 54 and surgical tool distal end 26 to advance out of thestraightening tube distal end 66 together as shown in FIG. 18 . Once theguide tube curved working end 54 reaches a desired orientation, thesurgical tool distal end 26 may be deployed from the guide tube distalend 56 by translating the surgical tool shaft 28 forward. Likewise, thesurgical tool distal end 26 may be retracted relative to the guide tube54 by reversing the translation direction of the surgical tool shaft 28.

In further embodiments, as shown in FIGS. 20 and 21 , the axial stop 80on straightening tube 60 engages a structure 83 outside of the workingchannel to stop the forward axial translation of the guide tube 50 andstraightening tube 60. When the axial stop 80 contacts structure 83, theforward translation of straightening tube 60 is stopped. In someembodiments, the relative locations of axial stop 80 and structure 83are positioned such that when contact is made, the straightening tubedistal end 66 and the guide tube distal end 56 are axially aligned withthe working channel distal end 19. From this position, the guide tube 50may be translated forward to extend the curved working end of the guidetube and to deploy the surgical tool distal end 26.

In some applications, during a surgical procedure, it is desirable toremove a surgical tool from the endoscope, resectoscope or trocarthrough the working channel while the device is positioned inside apatient's body without removing the endoscope, resectoscope or trocar.For example, a different surgical tool may be needed for a differentstage of an operation. To accommodate this, in some embodiments thepresent invention provides a concentric tube robot apparatus 90including a transmission 92 coupled to a tube array. The tube arrayincludes a guide tube 50 with a curved working end 54 housed inside astraightening tube 60. The guide tube 50 is straightened at leastpartially by the straightening tube 60 so that the tube array may beaxially inserted into or removed from a working channel on an endoscope,resectoscope or trocar.

Concentric tube robot apparatus 90 also includes a surgical tool with ashaft and an end effector housed within the guide tube 50. The guidetube 50 may be axially translated and rotated relative to thestraightening tube 60. The axial translation and rotation of the guidetube 50 is driven by a guide tube translation drive 94 a and a guidetube rotation drive 96 a. Each of the guide tube translation drive 94 aand guide tube rotation drive 96 a are mechanically coupled to guidetube 50 inside transmission 92. The guide tube translation drive 94 acontrols axial translation of guide tube 50 relative to straighteningtube 60. The guide tube rotation drive 96 a controls angular rotation ofguide tube 50 relative to straightening tube 60. Each guide tube drivemay be driven manually or using an electro-mechanical actuator such as agear box or motor.

Also shown in FIGS. 22 and 23 , in some embodiments, transmission 92also includes a surgical tool translation drive 94 b and a surgical toolrotation drive 96 b. The axial translation and rotation of the surgicaltool 20 relative to the guide tube 50 is controlled by the translationand rotation drives 94 b, 96 b, respectively.

When it is desired to change a surgical tool, a removable concentrictube robot apparatus 90, forming a removable cartridge, may be removedas a single unit from the device by sliding the tube array out of theworking channel. During removal, the straightening tube 60 is operableto constrain the curved working end of the guide tube enough tofacilitate removal of the tube array through the longitudinal workingchannel. A second concentric tube robot apparatus may be insertedthrough an insertion port, 72, shown in FIG. 24 , at the proximal end ofthe endoscope, resectoscope or trocar. The insertion port 72 provides anopening for insertion of the tube array and surgical tool assembly onthe concentric tube robot apparatus 90. In some embodiments, insertionport 72 includes a ramped surface including first and second ramps 74 a,74 b. In other embodiments, insertion port 72 includes an axisymmetricfunnel shaped to feed the distal tip of the tube array into the properlocation along the working channel longitudinal axis 36 for insertioninto and through the working channel 18.

Referring to FIGS. 25 and 26 , in additional embodiments, an endoscope,resectoscope or trocar includes a shaft 12 with a hollow interior. Theshaft 12 receives an optic element 34 such as a rod lens or opticalfiber that extends longitudinally through the shaft 12. Alternatively,optic element 34 can include a cable to a chip-tip style camerapositioned on the distal end of the working channel including lens 32. Aworking channel may be defined through the interior region on the shaftbelow the optical element 34 in some embodiments. In other embodiments,the working channel is defined in a cannula, or working channel insert17 a positioned inside the hollow interior of shaft 12. Additionally, asshown in FIG. 26 , in some applications it is desirable to include twosurgical tools with surgical tool distal ends 26 a, 26 b positioned inthe field of view of lens 32. Each surgical tool is housed within acorresponding guide tube. First surgical tool distal end 26 a and toolshaft 28 a extend from first guide tube curved working end 54 a. Secondsurgical tool distal end 26 b and tool shaft 28 b extend from secondguide tube curved working end 54 b. As shown in FIG. 26 , first andsecond tube arrays are positioned in separate working channels formed ina working channel insert 17 a having a working channel insert distal end19 a. The first tube array includes a straightening tube with a firststraightening tube distal end 66 a axially aligned with the distal end19 a of the working channel insert 17 a. Similarly, the second tubearray includes a straightening tube with a second straightening tubedistal end 66 b axially aligned with the distal end 19 a of the workingchannel insert 17 a. As such, the first and second straightening tubedistal ends 66 a, 66 b do not extend from the working channel openingsat the distal end of the working channel insert. A first guide tubecurved working end 54 a protrudes from the first straightening tubedistal end 66 a, and a second guide tube curved working end 54 bprotrudes from the second straightening tube distal end 66 b. Each guidetube and straightening tube may be rotated and translated. In someembodiments, each guide tube and straightening tube may be rotatedtogether. A first surgical tool distal end 26 a may be translated in andout of first guide tube curved working end 54 a, and second surgicaltool distal end 26 b may be translated in and out of second guide tubecurved working end 54 b.

A partial cross-sectional view of an embodiment of a shaft with firstand second tube arrays is shown in FIGS. 27 and 28 . Referring to FIG.27 , a first tube array 40 a is inserted in a first working channel 18a, and a second tube array 40 b is inserted in a second working channel18 b. The first and second tube arrays 40 a, 40 b each include astraightening tube 60 a, 60 b, a guide tube 50 a, 50 b and a surgicaltool 20 a, 20 b, respectively. First and second tube arrays 40 a, 40 bmay be inserted or removed independently of the other. In someembodiments, the first straightening tube 60 a of first tube array 40 amay be inserted to a position where the first straightening tube distalend 66 a is aligned with the working channel distal end 19. From thisposition, the first guide tube distal end 56 a and first surgical tooldistal end 26 a may be translated beyond the first straightening tubedistal end 66 a to deploy the first curved working end and firstsurgical tool end effector. Similarly, the second straightening tube 60b of the second tube array 40 b may be inserted to a position where thesecond straightening tube distal end 66 b is aligned with the workingchannel distal end. From this position, the second guide tube distal end56 b and second surgical tool distal end 26 b may be translated beyondthe second straightening tube distal end 66 b to deploy the secondcurved working end and second surgical tool end effector.

Referring further to FIG. 29 , in some embodiments a device forperforming minimally invasive surgery includes a shaft 12 includingshaft liner 13. A plenum 21 is defined between the shaft 12 and theshaft liner 13. In some embodiments, plenum 21 is used as a duct forsuction or irrigation. First and second working channels 18 a, 18 b aredefined inside the shaft. A first tube array is inserted in firstworking channel 18 a, and a second tube array is inserted in secondworking channel 18 b. The first tube array includes a firststraightening tube 60 a and a first guide tube 50 a positioned at leastpartially inside the first straightening tube. The first guide tubeincludes a first curved working end 54 a that is both axiallytranslatable and angularly rotatable relative to the first straighteningtube 60 a. First guide tube 50 a provides a guide to steer thepositioning of first surgical tool distal end 26 a. Depending on theaxial position and angular position of the first guide tube 50 a, firstsurgical tool distal end 26 a may be repositioned with precision inthree-dimensional space.

The second tube array includes a second straightening tube 60 b and asecond guide tube 50 b positioned at least partially inside the secondstraightening tube. The second guide tube includes a second curvedworking end 54 b that is both axially translatable and angularlyrotatable. Second guide tube 50 b provides a guide to steer thepositioning of second surgical tool distal end 26 b. Depending on theaxial position and angular position of the second guide tube 50 b,second surgical tool distal end 26 b may be repositioned with precisionin three-dimensional space.

As shown in FIG. 29 , in some embodiments, first and secondstraightening tube distal ends 66 a, 66 b do not extend beyond thedistal end 19 of first and second working channels. In some otherembodiments, first and second straightening tube distal ends 66 a, 66 bextend slightly beyond the distal end 19 of first and second workingchannels, but do not extend beyond the distal end of hood 15.

In further embodiments, the present invention includes a method ofperforming a surgical procedure, including the steps of (a) providing aconcentric tube robot including a guide tube with a curved tip and astraightening tube; (b) positioning the curved tip of the guide tubeinside the straightening tube; (c) inserting the guide tube andstraightening tube together into a working channel on an endoscopeshaft; (d) translating the guide tube relative to the straightening tubeto deploy the curved working end of the guide tube; and (e) translatinga surgical tool through the guide tube curved working end to a surgicalsite. The method further includes the steps of rotating the guide tuberelative to the straightening tube to reposition the surgical tool. Insome embodiments, the method further includes a step of retracting thecurved working end of the guide tube into the straightening tube andremoving the tube assembly from the working channel.

Thus, although there have been described herein particular embodimentsof the present invention of new and useful devices and methods forrobotic surgery, it is not intended that such references be construed aslimitations upon the scope of this invention except as set forth in thefollowing claims.

What is claimed is:
 1. An apparatus for performing surgery, comprising:a shaft including a longitudinal working channel defined through theshaft, the working channel having a proximal end with a proximal endopening and a distal end with a distal end opening and an inner workingchannel diameter; and an insertable tube assembly configured for axialinsertion into the longitudinal working channel, the insertable tubeassembly including a guide tube having a curved working end and a linearstraightening tube with an outer diameter, the curved working end of theguide tube having a resting orientation biased away from a longitudinalaxis of the linear straightening tube, the insertable tube assemblyincluding an effective outer diameter defined as the outer diameter ofthe insertable tube assembly when the guide tube is housed inside thelinear straightening tube, wherein when the curved working end of theguide tube is housed inside the linear straightening tube, the linearstraightening tube constrains and forces the curved working end of theguide tube away from its resting orientation toward the longitudinalaxis of the linear straightening tube. such that the effective outerdiameter of the insertable tube assembly is less than the inner workingchannel diameter, and such that the insertable tube assembly is straightalong the longitudinal axis of the linear straightening tube and may betranslated axially inside the longitudinal working channel.
 2. Theapparatus of claim 1, wherein the insertable tube assembly is configuredfor axial insertion into the proximal end opening of the workingchannel.
 3. The apparatus of claim 2, wherein the guide tube is axiallymoveable in translation relative to the linear straightening tube. 4.The apparatus of claim 3, wherein the guide tube is angularly rotatablerelative to the working channel.
 5. The apparatus of claim 4, furthercomprising a surgical tool disposed inside the guide tube.
 6. Theapparatus of claim 5, wherein the surgical tool is axially moveable intranslation relative to the guide tube.
 7. The apparatus of claim 6,wherein the surgical tool is angularly rotatable relative to the guidetube.
 8. The apparatus of claim 7, further comprising a transmissiondisposed on the insertable tube assembly, wherein the transmissionincludes a translation drive coupled to the guide tube and a rotationdrive coupled to the guide tube.
 9. The apparatus of claim 1, whereinthe curved working end of the guide tube is configured to bend towardthe resting orientation biased away from the longitudinal axis of thelinear straight tube in response to the curved working end of the guidetube being advanced out of the linear straightening tube.